提出了基质固相分散-高效液相色谱法测定袋泡茶中黄曲霉毒素B1、B2、G1和G2含量的方法。优化的试验条件为:① 样品与分散剂(中性氧化铝)的质量比为1比4;② 洗脱剂乙腈的用量为6 mL。以Symmetry C18色谱柱为分离柱,以甲醇-水(1+1)混合液为流动相进行分离。采用荧光检测,激发波长为365 nm,发射波长为435 nm。黄曲霉毒素B1、B2、G1和G2在一定的质量浓度范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.05~0.15 μg·L-1之间,测定下限(10S/N)在0.15~0.50 μg·L-1之间。以空白样品为基体进行加标回收试验,所得回收率在88.3%~96.8%之间,测定值的相对标准偏差(n=6)在4.3%~6.8%之间。

A method of HPLC for the determination of aflatoxins B1, B2, G1 and G2 in tea in bags with extraction by matrix solid phase dispersion was proposed. The optimized conditions found were as follows: ① mass ratio of sample to dispersant (neutral Al2O3): 1∶4;② volume of the eluant (acetonitrile) used: 6 mL. Symmetry C18 chromatographic column was used as stationary phase, and a mixture of methanol and water (1+1) was used as mobile phase in the separation. Fluorescence detection at the wavelengths of (λex) 365 nm and (λem) 435 nm was adopted in the determination. Linear relationships between values of peak area and mass concentration of aflatoxins B1, B2, G1 and G2 were kept in definite ranges, with detection limits (3S/N) in the range of 0.05-0.15 μg·L-1 and lower limits of determination (10S/N) in the range of 0.15-0.50 μg·L-1. On the base of blank sample, test for recovery was made by standard addition method;values of recovery found were in the range of 88.3%-96.8%, with RSD′s (n=6) in the range of 4.3%-6.8%.